关键词: 地热开发, 水化学动态, 影响原因

Abstract: Wang-3 and Wang-4 wells are two important wells for water chemistry observation in the Capital region. Whether or not the geothermal mining in Jingjinxincheng has influence to the two wells is of great significance to seismic regime monitoring. In this paper,based on the correlatability analysis of sharp pressure drop and water radon and water mercury changes caused by geothermal exploitation in Wang-3 and Wang-4 wells after July 2004 in Jingjinxincheng,we find that geothermal exploitation is the root cause of affecting earthquake observation in Wang-3 and Wang-4 wells despite different horizons and depths of geothermal aquifer and earthquake observation. Then,the author analyses the factors that influence the water chemistry behavior in Wang-3 and Wang-4 wells due to geothermal mining from the aspects of geological structure,development of Karst fissure,under-ground hydrodynamic condition,heat-dynamical condition,physical-chemistry equilibrium of underground water,and so on. Furthermore,the author puts forward some suggestions about site selection and construction of water chemistry observation well in geothermal anomaly area.

Key words: geothermal exploitation, water chemistry behavior, influencing factor